A known track-type mobile machine includes track assemblies on both the left side and the right side of the machine, which are used to propel the machine. In general, each track assembly includes a number of track links, connected to one another by track pins, to form an endless or closed track assembly. Shoes, which include grousers that are configured to contact the ground surface under the machine, are connected to the track links. On each side of the machine a sprocket that is driven to rotate by an engine of the machine engages the track assembly to translate the track assembly about spaced-apart pulley mechanisms. As the track links translate about the pulley mechanisms, the grousers of the shoes that are connected to the track links engage the ground surface to transmit torque from the sprockets to the ground surface in a direction opposite the desired travel direction of the machine, thereby propelling the machine. An implement, such as a bucket, a blade, or a fork, is often installed on the front of the machine to work (e.g., dig, shape, etc.) the ground surface or carry material (e.g., dirt, sand, stone, construction debris, pallets, etc.) over the ground surface.
When the track-type mobile machine is traveling straight forward or backward over the ground surface and no load is being exerted on the implement, the track assemblies slip relative to one another, such that the shoes and grousers on the left side and the right side of the machine end up in phase with one another. Thus, the grousers on the left side of the machine end up coming into and out of contact with the ground surface at the same time as the grousers on the right side of the machine. When the track assemblies are in phase, the machine may experiences a significant increase in vertical acceleration (e.g., approximately normal to the horizon), increasing undesired vibrations throughout the machine. These vibrations result in, for example, operator discomfort and fatigue, as well as decreased life of machine components.
U.S. Pat. No. 7,806,209 to Standish et al. is directed to an apparatus and a method to reduce vibrations on a tracked machine. In the Standish patent, each track assembly includes a repositionable roller. The rollers may be used to adjust the caternary hang for each of the track assemblies, so that they are not the same as one another, thereby resulting in reduced vibrations.
The system and the method of driving track assemblies in accordance with the current disclosure, however, may be used when a track-type mobile machine does not include repositionable rollers, and without adjusting caternary hang. The current disclosure may also overcome disadvantages resulting from other known systems and methods.